Hypodermic syringes



Feb. 24, 1959 s. N. BLACKMAN 2,874,694

HYPODERMIC SYRINGES Filed June 24, 1957 frag/vans United States Patent()HYPODERMIC SYRINGES Seymour N. Blackman, Teaneck, N. J., assignor toOmega Precision Medical Instrument Co., Inc., Passaic, N. J., acorporation of New Jersey Application June 24, 1957,` Serial No. 667,63314 Claims. (Cl. 12s-218) This invention relates to hypodermic syringes.

As is well known, the needles of hypodermic syringes conventionally areremoved for sterilization after each use. In addition, the needlesoccasionally are sharpened, and for dierent purposes different sizedneedles must be employed` The foregoing necessitates the use ofsterilizing and sharpening equipment which is both costly andtime-consuming to use. Still further, needles of many dilterent sizesmust always be kept ready to use.

It is an object of the present invention to provide a syringe which willobviate the need for field sterilization and 4sharpening equipment andfor resterilization of a needle after use. Y

It is another object of the'present inventionto provide a syringe of thecharacter described in which a needle of a given length has severalpredetermined elfective lengths, so that the syringe can be used for thedifferent purposes for which dilferent sized needles are requiredwithout changing the needles.

It is another object of-the present invention to provide a syringe ofthe character described which is sturdy and long-lasting. e

i It is another object of the present` invention to provide a syringe ofthe character described which is smoothworking and simple to useandinexpensive to manufacture. r

It is another object of the present invention to provide a syringe ofthe character described in which a resilient piston located in adisposable barrel is uniquelycouplable with an actuating stem inavmanner such that `the inter- ,engagement and disengagement of the stemand barrel is completely automatic.

It is another object of the present invention to provide i a syringe ofthe character described in which the resilient piston and the actuatingstem aresomutually constructed that, regardless of the material of thepiston, the sides thereof willpress against the walls of the barrel witha force sufficient to enable a substantial hydrostatic pressure to bedeveloped in the syringe. Y

It is an ancillaryobjectof the present invention to provide a syringe ofVthe character described having a disposable needle-carrying barrelwhich can Ibe located in any of a plurality of predetermined positionswith respect to a reusable frame. p

Other objects of thepinvpention will be in part obvious and in part willbe pointed out hereinafter.

The invention accordingly consists in features of construction,combinationsof elements and arrangements of parts which will beexemplified in the hypodermic syringe hereinaftern described and ofwhich` the scope of application will be indicated in the appendedclaims.

In the accompanying drawings, in which is shown one of the variouspossible embodiments of the invention,

Fig. l is an exploded perspective view of a syringe constructed inaccordance `with the instant invention;

Fig. 2 is an assembled perspective view thereof;

Fig. 3 is a sectional view taken substantially along the 2,874,694Patented Feb. 24, 1959' Fig. 4 is a fragmentary view similar to Fig. 3but illusl trating the piston coupled to the stem;

Fig. 5 is a sectional view taken substantially |along the line 5-,5 ofFig. 2;

Fig. 6 is a sectional View taken substantially along the line 6-6 ofFig. 3; and l Y Fig. 7 is a top view of the piston.

Referring now in detail to the drawings, the reference numeral 10denotes a hypodermic lsyringe constructed in accordance with the instantinvention. Said syringe includes two parts, to wit, a reusable frame 12and a disposable needle-carrying barrel 14. The lbarrel preferably isfabricated from' a pellucid synthetic and desirably a plastic which isheat sterilizable, e. g., a polyamide resin. The barrel has an open rearend 16` and a closed front end`18. The latter includes a through opening20 in which the base of a` hypodermic needle22 is tightly per- Vmanentlysecured. Diametrically opposite radially projec- The forward end of thepiston is closed and the rear end open. When the lbarrel is sold, thepiston is located in its open rear end asfshown'in Fig. 3. Pursuant to afeature of the invention, said piston includes laterally outwardlyextending integral protuberances, e. g., flanges 28, projecting fromadjacent the rear end beyond the Wall of the barrel. Desirably the side'walls of the piston Vare externally annular-1y ribbed.

` The reusable frame' preferably is fabricated from metal, e. g.stainless steel, although it can be made of a durable hard plastic, suchas a polyamide resin. The frame comprises 'a front end wall 30, afragmentary bottom wall 32 and a pair of curved side walls 34, 36 spacedapart a distance suicient for the barrel to be received between them.The side walls are joined at their tops by a tubular head section 38located at the rear end of the frame. The head section includes a capv40 from which finger ilanges 42 extend.

The bottom Wall has a forward opening 44 and the front Walla centralopening-.45, the two openings being connected by a wedge-shaped slot 46in the front wall. A series of bayonet slots 48 is provided along'theupper edge V"of, each side wall, each slot in one side wallbeingregistered with a slot in the other side wall. The bayonet slotsinclude upwardly extending vertical portions 50 and forwardly extendinghorizontal portions 52. The latter portions are non-circular in crosssection and are soa-dimen- Vsioned as to be capable ofsnugly slidablyand non-rotatably receiving the ears 24 of the barrel. Desirably theears and portions S2 likewise have rectangular cross-sections.

A stem 54 fabricated, for example, from metal is `journalledefor axiallyslidable movement dn the cap 40,

a bearing 56 being provided in the cap to guide the stem for forward andrearward movement. The plunger includes a thurrrbrest 60 at the rear endthereof andrav disc `62 at the front end. Said disc has a slightlylarger diamlongitudinal axis and that of the frame into coincidence, theneedle 22 first traversing the slot 46 and then entering the opening 4Sduring this operation. Now the barrel is shifted forwardly to bring theears against the bottom ofthe slots 48.

The next step is to move the stem .forwardly untilthe disc 62 there`ofafbuts vthe bottom of the piston;

To complete assembly of the syringe, thestem isnioved further forwardlyyto lock the disc 62 tothe piston. Continued forward movement of the stemcauses the piston to move forwardly, pulling the anges 23 into thebarrel. The latter is not large enough to accommodate the flanges sothat the anges swing or are compressed into the barrel behind the disc,as shown in Fig. 4. Due tol this arrangement it is impossibleaccidentally to` pull the piston ou't of the barrel. i

Attention is directed to the slightly oversize diameter of the disc 62.The piston 26 is asnug fit in the barrel. However, repeatedsterilization may somewhat lower the resiliency of the material of whichit is composed. Moreover, when the piston is fabricated frompolyethylene, it tends, after a time, to lessen its pressure'against thebarrel walls. Both of these difficulties are counteracted by theoversize disc which each time it enters the piston'expands the sameagainst the barrel.

The barrels are furnished empty and their needles' are in sterilecondition. The needles are protected against contamination in anyconventional way, as by' furnishing the entire barrel, including theneedle, in an air-tight container or by disposing a sleeve over theneedle alone. When it is desired to use the syringe, a 'barrel isselected and assembled to the carrier as described above. The stem ispushed all the way forward, the needle is inserted into the medicamentand the stem pulled back until sufficient medicament has been sucked upVinto the barrel. The medicament is injected into the patient'in theusual manner.

After a single use the barrel is discarded. To do this, the stem iswithdrawn as far as it will go so that the" disc is automaticallyuncoupled from the piston. The barrel then is tilted by pushing the backupwardly, andl the barrel is withdrawn from the frame.

It will be' apparent from the foregoing thatl a convenient and simpleconstruction has been provded-where by the costly and time-consuming'eld sterilizn'gand sharpening of hypodermic syringe needles iscompletely eliminated.

The provision of a plurality of pairs of registered bayonet slots in theframe enables the user of the syringe to vary the effective length ofthe needle in accordance with the requirements of the use to which thesyringe is to be put. Thus, a barrel having a needle with a fixed lengthcan be disposed and locked in lvarious positions in the frame wherebythe effective length of the needle, i. e., the length projecting fromthe frontend of the Vfratrie, is different. The number of differenteffective lengths` for any given actual length of needle will becontrolled by the number of ldifferent pairs of registered bayonetslots. Moreover, the distance between adjacent slots Vcan be varied andneed not be the same for each adjacent'pair of slots'.

It thus will be seen that there is provided a hypodermic syringe whichachieves the several objects of the invention'and is well adapted tomeet the conditions of practical use.

As various possible embodiments might be made of the above invention,and as `various'changes might be made in the embodiment above set forth,it is to be understood that all mattery herein described, or shown in'the accompanying drawings, is to be interpretedas illustrative 'and notin a limitingsense.

Having thus described' the invention, there is claimed as new anddesired to Vbe secured by Letters Patent:

l. `A hypodermic syringe comprisinga disposable'barrel havin'gfanope'nend and a closed end with athrough'aperture, a hypodermicV needlepermanently secured tothe closed end of the barrel with an end thereofin said aperture, said end having a bore communicating with the interiorof the barrel, an elongated reusable frame including a handle end and afront end, cooperating means associated with said barrel and frame fordetachably mounting said barrel in said frame in'. selectable positionsalong the longitudinal axis of the frame with said open end remote fromrthe frontl end of the frame, a piston in said barrel, a stem mounted inthe handle end of the frame for movement longitudinally of the frame,and cooperating means associated with the piston and stem for releasablycoupling the stem to the piston.

2. A hypodermic' syringeA comprising a disposable barrel having an openend and a closedv end with a through aperture, a hypodermic needlepermanently secured to the closed end of the barrel with an end thereofin said aperture, said end having a bore communicating with the interiorof the barrel, an elongated reusable frame including a handle end and afront end, cooperating means associated with saidl barrel and frame fordetachably mounting said barrel in said framein selectable positionsalong the longitudinal axisk of the frame with said open end remote fromthe frontend of the frame, the part of said means associated with thebarrel comprising diametrically oppositer'adially projecting ears on thebarrel adjacent the closed end thereof, and the part of the meansassociated with the frame comprising a series of angled slots disposedlongitudinally of the frame on each side thereof, each slot on one sidebeing registered with a slot on the other side, a piston in saidvbarrel, a stem mounted in the handle end of the frame for movementlongitudinally of the frame, and' cooperating means associated Withthepiston and stem for releasably coupling the stem to the piston; t

3. A hypodermic syringe comprising a disposable barrel having an openendl and a'crlosed end with a through aperture, a hypodermic needleApermanently secured tothe close'd end of the barrel with an end thereofin said aperture, said end having a bore communicating with the interiorof the barrel, an elongated reusable frame including alh'andle endand'alfront end, cooperating means associated 'with said'barrel and frame fordetachably mounting said barrel in said frame in selectable positionsalong the longitudinal axis of the frame with said'open end remotefrom'the front end of the frame, the part of said means associated withthe barrel com pris'ing diametrically opposite radially projecting earson the barrel-adjacent the closed end thereof, and the part of the meansassociated with the frame comprising a series of angledfslots disposedlongitudinally ofthe frame on each side thereof, each slot on one sidebeing registered with a slot on the other side, said angled slotsincluding upwardly extending'vertical portions and frontwardly extendinghorizontal portions, a piston in said barrel, a stem mounted in thehandle end of the frame for movement longitudinally ofthe frame, andcooperating means associatedwith the piston and stem for'releasablycoupling the stemto the piston.

4. A hypodermic syringe` comprising a' ldisposable barrel having anopen'end and a closed end with a through aperture, a hypodermic needlepermanently secured to the "clos'ed end-ofthe barrel with an end`thereof in said aperture, said'end Yhaving'a bore communicating with'the interiorV of the' barrel, an elongated reusable frame includingalhandle end 'and a front end, cooperating'=means associated withsadbarrel and frame for detachably mounting said 'barrel in said 'frame inselectable positions along the longitudinal'axis of the frame with saidopen end remote from the front end of the frame, an elastomeric -pistonin said barrel, a stem mounted in the handle end of the frame formovement longitudinally of the' frame, said piston including laterallyoutwardly extending pro'tubera'nces'.projecting beyond the wall of thebarrel from Aadjacent' the rear end thereof when the j pistovnandf'stemare in uncoupled condition,` said stem having an end facing the piston',said end having a diameterfless than the inner diametenof the barrelwhereby on forward movement of the stein said facing end abuts thepistonand moves the sainev forwardly in the barrel and entry of theprotuberances into the barrel releasably locks Vsaid endrof the stem tothe piston without relative rotationof the piston and" stem.

5 lA ,hypodermic syringe comprising a disposable barrel having `an openend and a closed end with a I facing the piston, said disc having alesserlength than the t through aperture, a hypodermic needlepermanently seeuredto the closed end of the barrel with an end thereofin said aperture, saidlendhaving a bore communicating with theinteriorroffthe barrel, an elongated reusable frame including a handleend and a front end, cooperating means associated with' said barrel andframe .for de tachably lmounting said barrel in said frame in selectable'positions along thelongitudinal axis of the frame with said ropen endremote from the front end of the frame, an elastomeric piston in saidbarrel, a stem `mounted in the'handle end of the`frame for movementlongitudinally 'of the frame, said piston including laterally outwardlyextending protuberances projecting beyond the wall of the barrel from4adjacent the rear end thereof lwhen the piston end stem are inuncoupled condition, said stem having an end facing `the piston, saidendhaving `a diameter less than the nnerdiameter of the barrel and beinglaterally engaged by the piston when the protuberances of the piston aredirected inwardly upon engagement of the protuberances-withfthebarrel-as theft-piston moves for wardly therein, whereby on forwardmovement of the stem, the stem and piston automatically are coupled andare automatically uncoupled onvreverse movement of the stem when thepiston reaches the open end of the barrel.

6. A hypodermic syringe comprising a disposable barrel having an openend and a closed end with a through aperture, a hypodermic needlepermanently secured to the closed end of the barrel with an end thereofin said aperture, said end having a bore communicating with the interiorof the barrel, an elongated reusable frame including a handle end and afront end, cooperating means associated with said barrel and frame fordetachably mounting said barrel in said frame in selectable positionsalong the longitudinal axis of the frame with said open end remote fromthe front end of the frame,

. j E 6. d thereof when the piston andstem aref in uncoupled con dition,said stem including a disc at` the end thereof inner length of the cupformed by Vthe piston and being receivable in the cup on forwardmovement of the stem, wherebyron forward movement thereof the disc abutsthe closed end of the piston and moves the same forwardly in the barreland entry of the protuberances into the barrel releasably locks the discto the piston.A f

8. A hypodermic syringe comprising a disposable barrel having an openend and a closed end with a through aperture, a hypodermic needlepermanently secured to the closed end of the barrel with an end thereofin said aperture, saidfend having a bore communicating with the interiorof the barrel, an elongated reusable frame including a handle end and` afront` end, cooperating means associated with said barrel andY frame fordetachably mounting said barrel in said frame in selectable positionsalongthe longitudinal axis of the frame with said open end remote fromthe front end of the frame, a cupshaped elastomeric piston in saidbarrel, a` stem mounted in the handle end of the frame for movementlongitudinally of the frame, theopen end of said piston facing the`handle end of saidV frame, said .piston including laterally outwardlyextending Vprotuberances projecting beyond the wall of the barrel Vfromadjacent the open end thereof when the piston and stem are in uncoupledcondition, said stem having a head facing ,the piston, said -head havinga lesser diameter than the inner diameter ofthe barrel, the side wall ofsaid piston having a greater thickness than the difference between thediameter of the head andthe inner diameter ofthe barrel, whereby.onvforward movement of the stemthe head abuts the piston and moves thesame forwardlyA inthe barrel and an elastomeric piston in said barrel, astem mounted in the handle end of the frame for movement longitudinallyof the frame, said piston including laterally outwardly extendingprotuberances projecting beyond the wall of the barrel from adjacent therear end thereof when the piston and stem are in uncoupled condition,said stem including a head facing the piston, said head having adiameter less than the inner diameter of the barrel, whereby on forwardmovement of the stern the head abuts the piston and moves the sameforwardly in the barrel and entry of the protuberances into the barrelreleasably locks the head to the piston.

7. A hypodermic syringe comprising a disposable barrel having an openend and a closed end with a through aperture, a hypodermic needlepermanently secured to the closed end of the barrel with an end thereofin said aperture, said end having a bore communicating with the interiorof the barrel, an elongated reusable frame including a handle end and afront end, cooperating means associated with said barrel and frame fordetachably mounting said barrel in said frame in selectable positionsalong the longitudinal axis of the frame with said open'end remote fromthe front end of the frame, a cup-shaped elastomeric piston in saidbarrel, a stem mounted in the handle end of the frame for movementlongitudinally of the frame, the open end of said piston facing thehandle end of said frame, said piston including laterally outwardlyextending protuberances projecting beyond the wall of the barrel fromadjacent the open end entry of the protuberances into the barrelreleasably locks the head to the piston, and said piston is expandedagainst the inner wall of the barrel so as to be snugly containedtherein.

9. In a hypodermic syringe, a barrel having an open end, an elongatedframe in which the barrel is detachably receivable, an elastomericpiston in said barrel, a stem mounted at the back of the frame formovement longitudinally of the frame, and means releasably coupling thepiston to the stem, said means comprising laterally outwardly extendingprotuberances projecting beyond the wall of the barrel from adjacent theopen end thereof when the piston and stem are in uncoupled condition,said means further comprising an end of said stem facing the piston andhaving a diameter less than the inner diameter of the barrel, whereby onforward movement of the stem, the stem and piston automatically arecoupled and are automatically uncoupled on reverse movement of the stemwhen the piston reaches the open Vend of the barrel.

10. In a hypodermic syringe, a barrel having an open end, an elongatedframe in which the barrel is detachably receivable, a cup-shapedelastomeric piston in said barrel, a stem mounted at the back of theframe for movement longitudinally of the frame, and means releasablycoupling the piston to the stem, said means comprising laterallyoutwardly extending protuberances projecting beyond the wall of thebarrel from adjacent the open end thereof when the piston and stem arein uncoupled condition, said means further comprising a head on` saidstem facing the piston and having a diameter less than the innerdiameter of the barrel, the side wall of said piston having a greaterthickness than the difference between the diameter of the head and theinner diameter of the barrel, whereby on forward movement of the stemthe head abuts the piston and moves the same forwardly in the barrel andentry of the protuberances into the barrel releasably locks the head tothe piston, and Ysaid piston is expanded against the inner wall of thebarrel so as to be snugly contained therein.

11. For use with a hypodermic syringe including an elongated reusablefratriey including a handle endgxanda frontv endl a' disposable' barrel"hyin'g a .f clo'sednend with a through aperture;4 hypod'er'inic needle`pferrjnanently seeured to Y s ai'denl o f the barrel with an en'dthereof in said aperture, aidji. `having a'boe communicating within@interior- `i the barrera stem' munj *d inthe handle end' of the formovement longitudinallyof the frame', a n d' m st onusaidv barrel`c'cope'fable with means on said frame for det'ah'ably mounting ,thebfarrel in selectable positionsalong the longitudinal axis of thefra'rne,y Vthe needlejprojejctiggfroin the front end of the frame' inall positions of thefbarrelin the frame. l2. For use' with a hypode'rmicsyringe including an elongated reusable frame including a handle end anda. fr bnt @ndgadsposabl handhaving a closed end with athroughLapertur'e', a hypoderrnic needle permanently secured tonsaidendof the barreliyith an end thereof in said aperture',saidfneedlehavinga A b'c'nfe communicating with the"V interiorpf the'barrel,^ a stern mounted in the handle end of the frarne for rnoyernentlongitudinally of the f raine,V and diarrietrically opposite radiallyproject'- ing ears onivsaid barrel cooperable with' rneans on lsaidVframe to' detachably n iount the barrel in selectable positionsv alongthe longitudinal axis of the frame, the needle projecting` fromv thefront end of vthe frame in all positions' vof the barrel Iin fthe frame.v

13.7*For use with a'hypoderniic Vsyringe including a disposable barrelhaving a closed end with a through aperture and a hypoderrnic needlelpermanently secured to said closed endtof the barrel ywith an endthereof in said ap ertu1 "e,'said needle having a bore communicatingwiththe interior of the barrel: an elongated reusable frame' including a'handleend and a front end, a stem mounted in the handle end formovementlongitudinally 0fA ,the .frame,and means iatedwith the frameaildeperab1e'with m`easj a` ltea with si'ci barr; rer detachablyJ mountingsaidbrrel in `Sf ,d fr'anie' in 4sf cftable positions" alrig thfezl"ngit'udi'na 'axis of they fratrie, theneedle projecting romjhe'endof'the fr'ar'ne in all positions of thev b arrel in fra1 1`1fe.

i4. 4For use with;p hpdfmie-1synge including adi;- pos'ble barrel havinga closed ,l'ld with a th'roiig'haiierture, .said barrelhavingdiainetrically opposite radially projecting ears, and a liypodermicneedle permanently secured to said closed end ofthe barrel with an endthereof in said aper'tire, sai d needle hayirig av bore orrirnunicatingwith the interior of lthe barrel.: an elongated reusable frame includinga handle end, 'a'.front endy and a. tubular slide wall having widelongitudinal slot,l a Stern rnount'ed in the handle endl o'f the frarnefor xiioveirient longitudinally lof thelfrain'e, Asaid fir-aine also'ineluding a series of separate narrow angled slots disposed longitudinally of the vframe on eachf side thereofandcornjniunicating withthe 'ed'gesof the 5101; for ySflugly' rg. ceiyi'rig said ears,eaehnarrow slot on one sideI being registered withav narrow Vslot onthemoth'er side, said registered narrow slots cooperating with said,ears l to de tachably rno'untthev barrel said frame inselectablepositionsalongnthe longitudinalaxis of 4vthe frani'e, the needleprojecting from the frontend of thefrarne in all positions of the barrelin the frame.

References inl l c?? I P aft. UNITED STATES PATENTS 1,529,659 Marcy Mar.17, 1925 2,068,927 Nevin Ian. 26, 1937 2,804,074 Hill Allg. 27, 19'57

